Replace the randomHex() function with separate functions

randomBlob() and hex(). (CVS 3620)

FossilOrigin-Name: f5ad74a9bc57e83c11beb3cf46bb6cd8c9de3f86

manifest

@@ -1,5 +1,5 @@
-C Add\sthe\srandomhex()\sfunction\sas\sa\sbuilt-in.\s(CVS\s3619)
+C Replace\sthe\srandomHex()\sfunction\swith\sseparate\sfunctions\nrandomBlob()\sand\shex().\s(CVS\s3620)
-D 2007-01-29T15:50:06
+D 2007-01-29T17:58:28
 F Makefile.in 7fa74bf4359aa899da5586e394d17735f221315f
 F Makefile.linux-gcc 2d8574d1ba75f129aba2019f0b959db380a90935
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -66,7 +66,7 @@ F src/date.c 393c73fc027597e008dcd81454544659e978b05c
 F src/delete.c 804384761144fe1a5035b99f4bd7d706976831bd
 F src/experimental.c 1b2d1a6cd62ecc39610e97670332ca073c50792b
 F src/expr.c 3d2cf15fd9aa6b60b67f45504782cce72cd07963
-F src/func.c 5df5260055fc8225df7daa4a6776763c78839a6a
+F src/func.c b7e1e220a6795ecae7649815145ea5f8644dfa5f
 F src/hash.c 449f3d6620193aa557f5d86cbc5cc6b87702b185
 F src/hash.h 1b3f7e2609141fd571f62199fc38687d262e9564
 F src/insert.c e9526ced19978a55687b55faea969b6ff2a53fb4
@@ -217,7 +217,7 @@ F test/fts2f.test b5f2dde48199d79e859f59d3d857c17dd62a0129
 F test/fts2g.test c69a8ab43ec77d123976ba6cf9422d647ae63032
 F test/fts2h.test 223af921323b409d4b5b18ff4e51619541b174bb
 F test/fts2i.test 1b22451d1f13f7c509baec620dc3a4a754885dd6
-F test/func.test a2a780de5f32fcdda3db9421281f87c7cf5f1077
+F test/func.test 71938e2ac704d8ce12f11810d475597640656ae9
 F test/hook.test 7e7645fd9a033f79cce8fdff151e32715e7ec50a
 F test/in.test 369cb2aa1eab02296b4ec470732fe8c131260b1d
 F test/index.test e65df12bed94b2903ee89987115e1578687e9266
@@ -406,7 +406,7 @@ F www/fullscanb.gif f7c94cb227f060511f8909e10f570157263e9a25
 F www/index-ex1-x-b.gif f9b1d85c3fa2435cf38b15970c7e3aa1edae23a3
 F www/index.tcl 7f67d421e4c1f48083c178bee460a27220f4fcc1
 F www/indirect1b1.gif adfca361d2df59e34f9c5cac52a670c2bfc303a1
-F www/lang.tcl ccbd38d9597117841b130287a19534b14dbf8990
+F www/lang.tcl aa6d599679cbd5612d7fd7b1ae733ac1221c2a76
 F www/lockingv3.tcl f59b19d6c8920a931f096699d6faaf61c05db55f
 F www/mingw.tcl d96b451568c5d28545fefe0c80bee3431c73f69c
 F www/nulls.tcl ec35193f92485b87b90a994a01d0171b58823fcf
@@ -428,7 +428,7 @@ F www/tclsqlite.tcl bb0d1357328a42b1993d78573e587c6dcbc964b9
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
-P 027251a6fc9971b337172436137fabdafec1d264
+P a6001589ab1349f7a6b4af941e9e0fd73d13c1c0
-R 26303d3b8e5ddcde80949e4541bf7afa
+R 81b8a9e1e2346eee4d0809c0a57c1d63
 U drh
-Z 353a878b84641f62bd1524ee3fc8f147
+Z e549908b92c57478539350b74a145cc3

manifest.uuid

@@ -1 +1 @@
-a6001589ab1349f7a6b4af941e9e0fd73d13c1c0
+f5ad74a9bc57e83c11beb3cf46bb6cd8c9de3f86

src/func.c

@@ -16,7 +16,7 @@
 ** sqliteRegisterBuildinFunctions() found at the bottom of the file.
 ** All other code has file scope.
 **
-** $Id: func.c,v 1.135 2007/01/29 15:50:06 drh Exp $
+** $Id: func.c,v 1.136 2007/01/29 17:58:28 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -273,30 +273,22 @@ static void randomFunc(
 }
 
 /*
-** Implementation of randomhex(N).  Return a random hexadecimal string
+** Implementation of randomblob(N).  Return a random blob
-** that is N characters long.
+** that is N bytes long.
 */
-static void randomHex(
+static void randomBlob(
   sqlite3_context *context,
   int argc,
   sqlite3_value **argv
 ){
-  int n, i, j;
+  int n;
-  unsigned char c, zBuf[1001];
+  unsigned char *p;
   assert( argc==1 );
   n = sqlite3_value_int(argv[0]);
-  if( n&1 ) n++;
+  if( n<1 ) n = 1;
-  if( n<2 ) n = 2;
+  p = sqlite3_malloc(n);
-  if( n>sizeof(zBuf)-1 )  n = sizeof(zBuf)-1;
+  sqlite3Randomness(n, p);
-  sqlite3Randomness(n/2, zBuf);
+  sqlite3_result_blob(context, (char*)p, n, sqlite3_free);
-  for(i=n-1, j=n/2-1; i>=1; i-=2, j--){
-    static const char zDigits[] = "0123456789ABCDEF";
-    c = zBuf[j];
-    zBuf[i] = zDigits[c&0xf];
-    zBuf[i-1] = zDigits[c>>4];
-  }
-  zBuf[n] = 0;
-  sqlite3_result_text(context, (char*)zBuf, n, SQLITE_TRANSIENT);
 }
 
 /*
@@ -575,6 +567,12 @@ static void versionFunc(
   sqlite3_result_text(context, sqlite3_version, -1, SQLITE_STATIC);
 }
 
+/* Array for converting from half-bytes (nybbles) into ASCII hex
+** digits. */
+static const char hexdigits[] = {
+  '0', '1', '2', '3', '4', '5', '6', '7',
+  '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' 
+};
 
 /*
 ** EXPERIMENTAL - This is not an official function.  The interface may
@@ -600,10 +598,6 @@ static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
       break;
     }
     case SQLITE_BLOB: {
-      static const char hexdigits[] = { 
-        '0', '1', '2', '3', '4', '5', '6', '7',
-        '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' 
-      };
       char *zText = 0;
       int nBlob = sqlite3_value_bytes(argv[0]);
       char const *zBlob = sqlite3_value_blob(argv[0]);
@@ -649,11 +643,41 @@ static void quoteFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
   }
 }
 
+/*
+** The hex() function.  Interpret the argument as a blob.  Return
+** a hexadecimal rendering as text.
+*/
+static void hexFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
+  int i, n;
+  const unsigned char *pBlob;
+  char *zHex, *z;
+  assert( argc==1 );
+  pBlob = sqlite3_value_blob(argv[0]);
+  n = sqlite3_value_bytes(argv[0]);
+  z = zHex = sqlite3_malloc(n*2 + 1);
+  if( zHex==0 ) return;
+  for(i=0; i<n; i++, pBlob++){
+    unsigned char c = *pBlob;
+    *(z++) = hexdigits[(c>>4)&0xf];
+    *(z++) = hexdigits[c&0xf];
+  }
+  *z = 0;
+  sqlite3_result_text(context, zHex, n*2, sqlite3_free);
+}
+
 #ifdef SQLITE_SOUNDEX
 /*
 ** Compute the soundex encoding of a word.
 */
-static void soundexFunc(sqlite3_context *context, int argc, sqlite3_value **argv){
+static void soundexFunc(
+  sqlite3_context *context,
+  int argc,
+  sqlite3_value **argv
+){
   char zResult[8];
   const u8 *zIn;
   int i, j;
@@ -1049,9 +1073,10 @@ void sqlite3RegisterBuiltinFunctions(sqlite3 *db){
     { "coalesce",          -1, 0, SQLITE_UTF8,    0, ifnullFunc },
     { "coalesce",           0, 0, SQLITE_UTF8,    0, 0          },
     { "coalesce",           1, 0, SQLITE_UTF8,    0, 0          },
+    { "hex",                1, 0, SQLITE_UTF8,    0, hexFunc    },
     { "ifnull",             2, 0, SQLITE_UTF8,    1, ifnullFunc },
     { "random",            -1, 0, SQLITE_UTF8,    0, randomFunc },
-    { "randomhex",          1, 0, SQLITE_UTF8,    0, randomHex  },
+    { "randomblob",         1, 0, SQLITE_UTF8,    0, randomBlob },
     { "nullif",             2, 0, SQLITE_UTF8,    1, nullifFunc },
     { "sqlite_version",     0, 0, SQLITE_UTF8,    0, versionFunc},
     { "quote",              1, 0, SQLITE_UTF8,    0, quoteFunc  },

test/func.test

@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is testing built-in functions.
 #
-# $Id: func.test,v 1.56 2007/01/29 15:50:06 drh Exp $
+# $Id: func.test,v 1.57 2007/01/29 17:58:28 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -303,21 +303,28 @@ do_test func-9.2 {
 } {integer}
 do_test func-9.3 {
   execsql {
-    SELECT randomhex(32) is not null;
+    SELECT randomblob(32) is not null;
   }
 } {1}
 do_test func-9.4 {
   execsql {
-    SELECT typeof(randomhex(32));
+    SELECT typeof(randomblob(32));
   }
-} {text}
+} {blob}
 do_test func-9.5 {
   execsql {
-    SELECT length(randomhex(32)), length(randomhex(-5)),
+    SELECT length(randomblob(32)), length(randomblob(-5)),
-           length(randomhex(2000)), length(randomhex(31));
+           length(randomblob(2000))
   }
-} {32 2 1000 32}
+} {32 1 2000}
 
+# The "hex()" function was added in order to be able to render blobs
+# generated by randomblob().  So this seems like a good place to test
+# hex().
+#
+do_test func-9.10 {
+  execsql {SELECT hex(x'00112233445566778899aAbBcCdDeEfF')}
+} {00112233445566778899AABBCCDDEEFF}
 
 # Use the "sqlite_register_test_function" TCL command which is part of
 # the text fixture in order to verify correct operation of some of

www/lang.tcl

@@ -1,7 +1,7 @@
 #
 # Run this Tcl script to generate the lang-*.html files.
 #
-set rcsid {$Id: lang.tcl,v 1.119 2007/01/29 15:50:06 drh Exp $}
+set rcsid {$Id: lang.tcl,v 1.120 2007/01/29 17:58:28 drh Exp $}
 source common.tcl
 
 if {[llength $argv]>0} {
@@ -1282,6 +1282,12 @@ both arguments are NULL then NULL is returned. This behaves the same as
 <b>coalesce()</b> above.</td>
 </tr>
 
+<tr>
+<td valign="top" align="right">hex(<i>X</i>)</td>
+<td valign="top">The argument is interpreted as a BLOB.  The result
+is a hexadecimal rendering of the content of that blob.</td>
+</tr>
+
 <tr>
 <td valign="top" align="right">last_insert_rowid()</td>
 <td valign="top">Return the ROWID of the last row insert from this
@@ -1374,12 +1380,9 @@ between -9223372036854775808 and +9223372036854775807.</td>
 </tr>
 
 <tr>
-<td valign="top" align="right">randomhex(<i>N</i>)</td>
+<td valign="top" align="right">randomblob(<i>N</i>)</td>
-<td valign="top">Return a pseudo-random hexadecimal string that is
+<td valign="top">Return a <i>N</i>-byte blob containing pseudo-random bytes.
-<i>N</i> characters in length.  <i>N</i> should be an even integer between
+<i>N</i> should be a postive integer.</td>
-2 and 1000.  The intended use of this function is to generate
-universally unique identifiers (UUID).  For that purpose, it is recommended
-that <i>N</i> be at least 32.</td>
 </tr>
 
 <tr>